170

170 is a natural number that follows 169 and precedes 171. In mathematics, it is even and composite. Its prime factorization is 2 × 5 × 17, so it is the product of three distinct primes, a property known as being a sphenic number. The divisors of 170 are 1, 2, 5, 10, 17, 34, 85, and 170. The sum of its proper divisors is 154, making it a deficient number (the sum of proper divisors is less than the number itself).

In numeral systems, 170 is written as 10101010 in binary, AA in hexadecimal, and 252 in octal. In Roman numerals it is CLXX.

170 has the relation to triangular numbers in that it is one less than 171, which is the 18th triangular number (T18). This places 170 near a key sequence in the study of figurate numbers, illustrating how certain integers relate to simple geometric progressions.

As a number, 170 appears in a variety of standard counting and labeling tasks, and it serves as a concrete example of how prime factorization, divisor sums, and base representations can illuminate the structure of integers.